'Unlawful combatants'

The Israeli Prison Service refuses to transfer him to a civilian hospital for proper treatmentPhysicians for Human Rights-Israel

"Despite the urgency of his condition, the Israeli Prison Service (IPS) has denied Mahmoud access to independent doctors from PHR-Israel until today," a statement said.

"The IPS also refuses to transfer him to a civilian hospital for proper treatment."

PHR-Israel said Mr Sarsak had lost 33% of his body weight, and suffers from frequent incidents of fainting and loss of consciousness, in addition to lapses in memory.

An Israeli government official told the BBC that Israel "does not wish to see any prisoners have their health put at risk".

"This is precisely why we made huge efforts to end the recent strike, with the co-operation in terms agreed with the prisoners themselves, the Palestinian Authority and other organisations.

"Sadly, Sarsak chose to exclude himself from this agreement, preferring to put his own life at risk. We are providing him with all required medical treatment, but hope he will join his fellow prisoners and end his strike."

The 25-year-old footballer was once regarded as a star player in the Palestine national side.

For three years he has been held under Israel's so-called "Unlawful Combatants Law", which allows for Palestinians from Gaza to be detained for an unlimited time without charge or trial.

PHR-Israel said those detained under the statute had little or no legal protections, even less than those detained under "administrative detention" orders in the West Bank.

Amnesty International
issued a new report
on Wednesday strongly condemning administrative detention.

Image caption
Israel says many of the Palestinian prisoners are suspected of being members of militant groups

The human rights group said administrative detainees had been "subjected to violations such as the use of torture and other ill-treatment during interrogation, as well as cruel and degrading treatment during their detention, sometimes as punishment for hunger strikes or other protests".

Israeli government spokesman Mark Regev said administrative detention was only used as a last resort, and to help avoid retribution.

"If we get information from someone whose neighbour is making explosives for suicide bombers and that evidence is presented in court, then terror groups will take violent action against him and his family," Mr Regev told the Associated Press.

"Administrative detention is specifically allowed under international law, and it is factually incorrect to say otherwise," he said.

As of the end of April there were at least 308 Palestinian administrative detainees, among them 24 members of the Palestinian Legislative Council (PLC), Amnesty said.

Israel says that many of 4,500 Palestinian prisoners in its jails are suspected of being members of Palestinian militant groups.